The continuous market pressures to produce integrated circuits (ICs), such as memory ICs and CPUs, more cost-effectively necessitates a rapid and cost-effective way to systematically manage testing of ICs and the corresponding test results at various stages of the manufacturing process such as testing at wafer level, quality assurance (QA), and at package level, as well as maintaining inventory information at various stages. For example, if information on the test results at the wafer level is recorded for each integrated circuit and is readily accessible, efficiency at subsequent stages will be enhanced. Similarly, recordation of the test results at the next stage in turn accelerates the efficiency at subsequent stages. Thus, the general work efficiency can be greatly improved by recording the operation results at each intermediate stage and continuously updating the information at each stage.
Also, the ability to retrieve the test results as well as tracking information (e.g., fab location, manufacturing technology, year of manufacturing, wafer lot, wafer number, location of the IC on the wafer, packaging plant, type of package) recorded in each IC can be highly beneficial in aiding yield improvement efforts. Further, manufacturing semiconductor chips as value-added products has been a recent trend and, this trend will be more pronounced in the future.
Hence, there is a need for efficient and cost-effective management of information at various stages of IC manufacturing and production and beyond.